3 # Test case for image corruption (overlapping data structures) in qcow2
5 # Copyright (C) 2013 Red Hat, Inc.
7 # This program is free software; you can redistribute it and/or modify
8 # it under the terms of the GNU General Public License as published by
9 # the Free Software Foundation; either version 2 of the License, or
10 # (at your option) any later version.
12 # This program is distributed in the hope that it will be useful,
13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 # GNU General Public License for more details.
17 # You should have received a copy of the GNU General Public License
18 # along with this program. If not, see <http://www.gnu.org/licenses/>.
22 owner
=mreitz@redhat.com
25 echo "QA output created by $seq"
29 status
=1 # failure is the default!
35 trap "_cleanup; exit \$status" 0 1 2 3 15
37 # get standard environment, filters and checks
41 # This tests qocw2-specific low-level functionality
46 rt_offset
=65536 # 0x10000 (XXX: just an assumption)
47 rb_offset
=131072 # 0x20000 (XXX: just an assumption)
48 l1_offset
=196608 # 0x30000 (XXX: just an assumption)
49 l2_offset
=262144 # 0x40000 (XXX: just an assumption)
50 l2_offset_after_snapshot
=524288 # 0x80000 (XXX: just an assumption)
54 OPEN_RW
="open -o overlap-check=all $TEST_IMG"
55 # Overlap checks are done before write operations only, therefore opening an
56 # image read-only makes the overlap-check option irrelevant
57 OPEN_RO
="open -r $TEST_IMG"
60 echo "=== Testing L2 reference into L1 ==="
63 # Link first L1 entry (first L2 table) onto itself
64 # (Note the MSb in the L1 entry is set, ensuring the refcount is one - else any
65 # later write will result in a COW operation, effectively ruining this attempt
66 # on image corruption)
67 poke_file
"$TEST_IMG" "$l1_offset" "\x80\x00\x00\x00\x00\x03\x00\x00"
70 # The corrupt bit should not be set anyway
71 $PYTHON qcow2.py
"$TEST_IMG" dump-header |
grep incompatible_features
73 # Try to write something, thereby forcing the corrupt bit to be set
74 $QEMU_IO -c "$OPEN_RW" -c "write -P 0x2a 0 512" | _filter_qemu_io
76 # The corrupt bit must now be set
77 $PYTHON qcow2.py
"$TEST_IMG" dump-header |
grep incompatible_features
79 # Try to open the image R/W (which should fail)
80 $QEMU_IO -c "$OPEN_RW" -c "read 0 512" 2>&1 | _filter_qemu_io \
84 # Try to open it RO (which should succeed)
85 $QEMU_IO -c "$OPEN_RO" -c "read 0 512" | _filter_qemu_io
87 # We could now try to fix the image, but this would probably fail (how should an
88 # L2 table linked onto the L1 table be fixed?)
91 echo "=== Testing cluster data reference into refcount block ==="
95 truncate
-s "$(($l2_offset+65536))" "$TEST_IMG"
96 poke_file
"$TEST_IMG" "$l1_offset" "\x80\x00\x00\x00\x00\x04\x00\x00"
97 # Mark cluster as used
98 poke_file
"$TEST_IMG" "$(($rb_offset+8))" "\x00\x01"
99 # Redirect new data cluster onto refcount block
100 poke_file
"$TEST_IMG" "$l2_offset" "\x80\x00\x00\x00\x00\x02\x00\x00"
102 $PYTHON qcow2.py
"$TEST_IMG" dump-header |
grep incompatible_features
103 $QEMU_IO -c "$OPEN_RW" -c "write -P 0x2a 0 512" | _filter_qemu_io
104 $PYTHON qcow2.py
"$TEST_IMG" dump-header |
grep incompatible_features
107 _check_test_img
-r all
109 # The corrupt bit should be cleared
110 $PYTHON qcow2.py
"$TEST_IMG" dump-header |
grep incompatible_features
112 # Look if it's really really fixed
113 $QEMU_IO -c "$OPEN_RW" -c "write -P 0x2a 0 512" | _filter_qemu_io
114 $PYTHON qcow2.py
"$TEST_IMG" dump-header |
grep incompatible_features
117 echo "=== Testing cluster data reference into inactive L2 table ==="
120 $QEMU_IO -c "$OPEN_RW" -c "write -P 1 0 512" | _filter_qemu_io
121 $QEMU_IMG snapshot
-c foo
"$TEST_IMG"
122 $QEMU_IO -c "$OPEN_RW" -c "write -P 2 0 512" | _filter_qemu_io
123 # The inactive L2 table remains at its old offset
124 poke_file
"$TEST_IMG" "$l2_offset_after_snapshot" \
125 "\x80\x00\x00\x00\x00\x04\x00\x00"
127 $PYTHON qcow2.py
"$TEST_IMG" dump-header |
grep incompatible_features
128 $QEMU_IO -c "$OPEN_RW" -c "write -P 3 0 512" | _filter_qemu_io
129 $PYTHON qcow2.py
"$TEST_IMG" dump-header |
grep incompatible_features
130 _check_test_img
-r all
131 $PYTHON qcow2.py
"$TEST_IMG" dump-header |
grep incompatible_features
132 $QEMU_IO -c "$OPEN_RW" -c "write -P 4 0 512" | _filter_qemu_io
133 $PYTHON qcow2.py
"$TEST_IMG" dump-header |
grep incompatible_features
136 $QEMU_IO -c "$OPEN_RO" -c "read -P 4 0 512" | _filter_qemu_io
137 $QEMU_IMG snapshot
-a foo
"$TEST_IMG"
139 $QEMU_IO -c "$OPEN_RO" -c "read -P 1 0 512" | _filter_qemu_io
142 echo "=== Testing overlap while COW is in flight ==="
144 # compat=0.10 is required in order to make the following discard actually
145 # unallocate the sector rather than make it a zero sector - we want COW, after
147 IMGOPTS
='compat=0.10' _make_test_img
1G
148 # Write two clusters, the second one enforces creation of an L2 table after
149 # the first data cluster.
150 $QEMU_IO -c 'write 0k 64k' -c 'write 512M 64k' "$TEST_IMG" | _filter_qemu_io
151 # Discard the first cluster. This cluster will soon enough be reallocated and
153 $QEMU_IO -c 'discard 0k 64k' "$TEST_IMG" | _filter_qemu_io
154 # Now, corrupt the image by marking the second L2 table cluster as free.
155 poke_file
"$TEST_IMG" '131084' "\x00\x00" # 0x2000c
156 # Start a write operation requiring COW on the image stopping it right before
157 # doing the read; then, trigger the corruption prevention by writing anything to
158 # any unallocated cluster, leading to an attempt to overwrite the second L2
159 # table. Finally, resume the COW write and see it fail (but not crash).
160 echo "open -o file.driver=blkdebug $TEST_IMG
165 resume 0" |
$QEMU_IO | _filter_qemu_io
168 echo "=== Testing unallocated image header ==="
172 $QEMU_IO -c "$OPEN_RW" -c "write 0 64k" | _filter_qemu_io
173 poke_file
"$TEST_IMG" "$rb_offset" "\x00\x00"
174 $QEMU_IO -c "$OPEN_RW" -c "write 64k 64k" | _filter_qemu_io